1. Field of the Invention
The present invention generally relates to a slew rate enhancing circuit, and more particularly to a slew rate enhancing circuit for an operational amplifier.
2. Description of Related Art
An operational amplifier (OPA) is one type of differential amplifier that is one of the widely used electronic circuits for constructing a variety of modern electronic systems. It is common to use Miller capacitors for frequency compensation in the OPA to improve the stability of the OPA. However, the Miller capacitor with large capacitance disadvantageously degrades the slew rate of the OPA, and therefore restricts the operating speed of the OPA. Accordingly, tradeoff should be confronted between the stability and slew rate when designing the OPA.
For the reason that conventional OPAs are either limited by the low slew rate or unstable, a need has arisen to propose a novel slew rate enhancing circuit for improving operating speed of an amplifier by boosting its slew rate without degrading its stability.